Expandable ablation burr

• US 20040158270A1
• Filed: 02/02/2004
• Published: 08/12/2004
• Est. Priority Date: 03/05/1998
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Inventors: Chen, John J., Wang, Lixiao, Zhong, Sheng-Ping, Nazarova, Irina, Haig, Nancy L., Wyzgala, Mark H., Hamilton, Eric B., Hiblar, Thomas J.
• Granted Patent: US 7,252,674 B2
• Time in Patent Office: Days
• US Class Current: 606/170
• CPC Class Codes: A61B 17/320725 with radially expandable cutting or abrading elements A61B17/32075 takes precedence
• CPC Class Codes: A61B 17/320758 with a rotating cutting instrument, e.g. motor driven A61B17/320725, A61B17/32075 and A61B17/320783 take precedence; for removing intra-ocular material A61F9/00763; endoscopic rotatable cutting instruments A61B17/32002
• CPC Class Codes: A61B 2017/00557 inflatable A61B2017/22051 takes precedence
• CPC Class Codes: A61B 2017/00867 shape memory effect
• CPC Class Codes: A61B 2017/320004 abrasive
• CPC Class Codes: A61B 2017/320733 with a flexible cutting or scraping element, e.g. with a whip-like distal filament member

Abstract

An atherectomy burr has an operating diameter that is larger than the diameter of a catheter in which the burr is routed. The burr may include a polymeric balloon that is coated with an abrasive and that expands when the burr is rotated. When the burr is rotated, the polymeric tube expands by centrifugal force. The maximum expansion of the burr is controlled by an expansion mechanism. Various mechanisms are disclosed for controlling the maximum diameter of the burr thus preventing the burr from over expanding. In addition, the present invention includes a system for preventing the loose ablated particulate from reembolizing in the distal vasculature. The system includes an ablation burr that has abrasive disposed on the proximal end that is pulled back toward the guide catheter to ablate the lesion. The burr creates a seal when expanded to block the ablated particulate so that the aspiration system can remove the particulate from the patient vessel or stent. Alternatively, the burr system may include a self expanding seal that is deployed out of the aspiration sheath so that a slight vacuum can remove the large loose particulate form, the patient'"'"'s vessel or stent.

Claims

1. A device for ablating an occlusion in a patient'"'"'s blood vessel, comprising:

a drive shaft;

an ablation burr secured to the drive shaft, the ablation burr comprising a polymeric tube section, the polymeric tube section being expandable from an unexpanded state with a first diameter to an expanded state with a second larger diameter, the polymeric tube section having an abrasive coating disposed on at least a portion of its exterior surface to ablate an occlusion in a patient'"'"'s vessel; and

an expansion control system to control the expansion of the burr to a predetermined expanded diameter when in the expanded state.

2. The device of claim 1, wherein the expansion control system is embedded within the polymeric tube section.

3. The device of claim 2, wherein the expansion control system comprises fibers arranged in a braided configuration.

4. The device of claim 2, wherein the expansion control system comprises a film layer.

5. The device of claim 4, wherein the film layer is an expanded Polytetraflouroethylene.

6. The device of claim 1, wherein the polymeric tube section assumes the expanded state when rotated by the drive shaft.

7. The device of claim 1, wherein the expansion control system comprises internal curvilinear ribs disposed on the inside surface of the polymeric tube section.

8. The device of claim 7, wherein the curvilinear ribs straighten toward a linear configuration to control the expansion of the burr.

9. The atherectomy device of claim 1, wherein the polymeric tube section is post cross-linked, the post cross-linked polymeric tube section functioning as the expansion control system of the atherectomy device.

10. The device of claim 1, wherein the expansion control system comprises a first layer of fiber within the polymeric tube section disposed in a first direction, and a second layer of fiber within the polymeric tube section disposed in a second direction that is opposite of the first direction.

29. The reverse pull-back device according to claim 8, wherein the polymeric balloon section has a distal end portion and a proximal end portion and includes a wire mesh disposed within the polymeric balloon section, the wire mesh beginning at the proximal end portion of the balloon section and extending to about the midpoint of the ablation burr so that the proximal end portion of the balloon section forms a concave shaped portion.

30. The reverse pull-back device according to claim 9, wherein the abrasive is coated on the wire mesh in the expanded state.

11. An device for ablating an occlusion in a patient'"'"'s blood vessel, comprising:

a drive shaft;

an ablation burr secured to the drive shaft, the burr including a nose section having a fixed maximum diameter and an expandable polymeric section having an abrasive disposed on at least a portion thereof, the polymeric section having a diameter that increases as the rotational speed of the drive shaft increases;

wherein the polymeric section includes a system that limits the expansion of the burr to a predetermined maximum diameter.

12. The atherectomy device of claim 11, wherein the nose section of the ablation burr having a maximum diameter includes a stepped portion disposed at the proximal end of the nose section and having a substantially constant diameter that is smaller than the maximum diameter of the nose section, and wherein the polymeric section comprises a tube disposed over the stepped portion of the nose section.

13. The atherectomy device of claim 12, wherein the ablation burr further includes an end section having a fixed maximum diameter, the end section of the ablation burr includes a stepped portion disposed at the distal end of the end section and having a substantially constant diameter that is smaller than the maximum diameter of the end section, the polymeric tube section disposed over the stepped portion of the end section.

14. A reverse pull-back device for ablating a lesion in a patient'"'"'s blood vessel or stent, comprising:

a drive shaft;

an ablation burr secured to the drive shaft, the ablation burr comprising a polymeric balloon section, the polymeric balloon section having an unexpanded state with a first diameter and an expanded state with a second larger diameter, the polymeric balloon section having an abrasive coating disposed on at least a portion of its exterior surface to ablate a lesion in a patient'"'"'s vessel or stent;

wherein the balloon section is expandable to create a seal with the vessel or stent when in the expanded state.

15. The reverse pull-back device according to claim 14, wherein the polymeric balloon section has a proximal end portion and a distal end portion, and wherein the abrasive is disposed on the outer surface of the proximal end portion of the polymeric balloon section.

16. The reverse pull-back device according to claim 15, wherein the ablation burr includes a smooth section on the distal end portion of the polymeric balloon section so that the ablation burr does not irritate the patient'"'"'s vessel or stent when the ablation burr is rotating in the expanded state.

17. The reverse pull-back device according to claim 14, wherein the device further comprises an aspiration catheter to remove the ablated lesion from the patient'"'"'s vessel or stent.

18. The reverse pull-back device according to claim 14 wherein the balloon section unfurls to the expanded state as the drive shaft is rotated.

19. A method for ablating a lesion or occlusion in a patient'"'"'s vessel or stent comprising:

routing an ablation burr in an unexpanded state over a guide wire to a position distal to the lesion;

rotating a drive shaft to begin the expansion of the ablation bur;

pulling the ablation burr in an expanded state proximally toward to the lesion;

ablating the lesion with the ablation burr as the ablation burr passes through the lesion.

20. The method according to claim 19, further comprising the step of removing the ablated material from the patient'"'"'s vessel or stent through an aspiration catheter.

21. The method according to claim 19, further comprising the step of deploying a self-expanding seal from within an aspiration catheter after the ablation burr begins to expand.

22. The method according to claim 19, wherein the ablation burr includes a balloon section, the balloon section creating a seal with the vessel or stent when in the expanded state.

23. A method for ablating a lesion in a patient'"'"'s vessel or stent with the use of a reverse pull-back ablation system, the ablation system comprising a drive shaft, an aspiration catheter disposed around the drive shaft, and an ablation burr secured to the drive shaft, the ablation burr comprising a polymeric balloon section, the polymeric balloon section having an unexpanded state with a first diameter and an expanded state with a second larger diameter, the polymeric balloon section having an abrasive coating disposed on at least a portion of its exterior surface to ablate a lesion in a patient'"'"'s vessel or stent, and a lumen extending through the drive shaft and ablation burr for receiving a guide wire, the method comprising:

routing the ablation burr in an unexpanded state over the guide wire to a position distal to the lesion;

rotating the drive shaft to begin the expansion of the ablation bur;

pulling the ablation burr in an expanded state toward a position proximal to the lesion; and

ablating the lesion with the ablation burr as the ablation burr passes through the lesion.

24. The method according to claim 23, further comprising the step of removing the ablated material from the patient'"'"'s vessel or stent through the aspiration catheter.

25. The method according to claim 23, further comprising the step of deploying a self-expanding seal from within the aspiration catheter after the ablation burr begins to expand.

26. The method according to claim 23, wherein the ablation bur has a forward cutting surface when in the unexpanded state.

27. The method according to claim 23, wherein the step of routing the ablation burr includes cutting a lumen through the lesion so that the ablation burr may be routed to the position distal to the lesion.

28. A reverse pull-back device for ablating a lesion in a patient'"'"'s blood vessel or stent, comprising:

a drive shaft;

an ablation burr secured to the drive shaft, the ablation burr comprising a polymeric balloon section, the polymeric balloon section having an unexpanded state with a first diameter and an expanded state with a second larger diameter, the polymeric balloon section having an abrasive coating disposed on at least a portion of its exterior surface to ablate a lesion in a patient'"'"'s vessel or stent; and

an aspiration catheter disposed around the drive shaft to remove the ablated material from the lesion.

31. The reverse pull-back device according to claim 28, further comprising a self-expanding seal coupled to the aspiration catheter.